Fastener

ABSTRACT

A fastener comprises an anchor and a central pin. The anchor has a top plate to which a central leg is connected. At the free end of the central leg are two anchor arms that extend up and outward from the free end, forming an arrowhead shape. The anchor arms are flexible and can flex inward as the anchor is placed through a hole in an item to be fastened. Connected to the top surface of the top plate is a push pin. Depressing the push pin breaks the connection areas to create a two-piece anchor from the single part. The push pin comprises a push button and a pin connected to the underside of the push button. The pin consists of a vertical post having a channel therein for accommodating the central leg of the anchor. Pushing the push button downward causes the anchor arms to be pushed outward and to anchor the fastener into the items to be fastened.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] This invention relates to a fastener for fastening two planarobjects together. In particular, the invention relates to a fastenercomprising an anchor and a push pin that is particularly useful forfastening automotive body panels to sheet metal.

[0003] 2. The Prior Art

[0004] Anchor type fasteners having a central pin are known. Forexample, U.S. Pat. No. 4,571,134 to Seglinger et al. shows a two-pieceplastic fastener comprising an anchor and a central pin. The anchorcomprises a closed V-shaped insertion portion and a top plate. Theanchor is placed through two (or more) planar items to be fastenedtogether. A central pin extends down between the arms of the V andcauses the arms to spread when the pin is fully depressed. Thisspreading anchors the fastener in the rear item and prevents thefastener from coming out. The plate prevents the front item from comingaway from the rear item. While this type of fastener is widely used, theclosed V-shape of the anchor makes it difficult to install. This isbecause a large amount of force is required to cause the arms of the Vto bend inward sufficiently to pass through an aperture in the item tobe mounted, and outward sufficiently enough to let the pin extend to itsfully inserted position and retain the anchor in the item. The anchormust bend enough during insertion of the pin so as to prevent the anchorfrom being inadvertently pulled out by a counter force acting on theitems.

[0005] Other fasteners using the same concept are shown in U.S. Pat.Nos. 6,533,515, 6,074,144 and 5,775,860 all to Meyer, as well as U.S.Pat. No. 6,045,309 to LeVey. These fasteners all suffer the samedrawback as Beglinger: the closed V formation of the anchor is soresistant to bending that a large amount of force is required to insertthe fastener, and bring it into a locked position.

[0006] A plastic fastener having a different configuration is shown inU.S. Pat. No. 4,085,651 to Koscik. In this fastener, the anchor consistsof two parallel legs that extend below the plate. Depressing the centerpin forces the legs to bend outwards and retain the fastener in theitem. This fastener suffers the drawback that the parallel legs are moredifficult to insert into a small aperture in the item, as they mustoften be squeezed together by the operator's fingers in order for theanchor to be inserted.

[0007] In large capacity use, such as automobile assembly lines, it isimperative that the fasteners used to attach body panels to theautomobile frame be quick and easy to install in large quantities. Sincethe fasteners are inserted by hand, they should not require undue forceto complete the insertion, due to operator fatigue. They should also beable to be installed using a minimum number of steps.

SUMMARY OF THE INVENTION

[0008] It is therefore an object of the invention to provide a fastenerthat is simple to install with a low amount of force.

[0009] It is another object of the invention to provide a fastener thatis strong and reliable.

[0010] It is another object of the invention to provide a fastener thatdoes not require assembly prior to use.

[0011] It is yet another object of the invention to provide a fastenerthat is simple and inexpensive to manufacture.

[0012] These and other objects are accomplished by a fastener comprisingan anchor and a central pin. The anchor comprises a top plate to which acentral leg is connected. The central leg extends perpendicularly downfrom the top plate. At the free end of the central leg are two anchorarms that extend up and outward from the free end, forming an arrowheadshape. Each anchor arm has a free end facing upward. The anchor arms areflexible and can flex inward as the anchor is placed through a hole inan item to be fastened.

[0013] Connected to the top surface of the top plate is a push pinassembly. The push pin assembly is integrally molded with the topsurface of the top plate via small connection areas. This way, only asingle mold is required for molding the fastener. Depressing the pushpin breaks the connection areas to create a two-piece anchor from thesingle part. The push pin comprises a push button and a pin connected tothe underside of the push button. The pin consists of a vertical posthaving a channel therein for accommodating the central leg of theanchor. Pushing the push button downward causes the pin to slide alongthe central leg until the end of the pin abuts the inner surface of theanchor legs. This causes the anchor arms to be pushed outward and toanchor the fastener into the items to be fastened.

[0014] Extending down from the top plate on either side of the centralleg are two retaining arms. Each retaining arm has a structure thatinteracts with a corresponding structure on the anchor legs as they areforced outward to prevent the anchor arms from extending beyond apredetermined limit. This prevents the anchor arms from being bententirely back by a sudden force and breaking. The interacting structurescould be interacting hooks, protrusions or any other structure thatwould prevent the anchor arms from moving beyond the retaining arms. Theoutside surfaces of the retaining arms are suited to center the fastenerwithin the hole of the panel.

[0015] Preferably, there are guide flanges located on an inner surfaceof the anchor arms, that guide the pin and keep it aligned with thecentral leg as it slides down toward the bottom of the anchor. Theflanges extend out around one side of the anchor, on the opposite faceof the pin from the channel, to prevent the pin from moving laterallybeyond a predetermined limit. The pin has a notch cut into its lowerend. When the bottom of the pin contacts the guide flange, the flangesnaps into the notch and prevents upward movement of the pin. Anadditional notch and flange arrangement is located higher up on the pinand anchor assembly and also snaps closed to provide further insuranceagainst upward movement of the pin after the fastener is in its fullylocked position.

[0016] Preferably, the fastener can be set to a pre-loaded state priorto insertion into the items to be fastened. When the fastener is firstmolded, the pin is integrally formed with the anchor and extends upthough an aperture in the top plate. The aperture is preferably U-shapedto accommodate the channel-containing pin structure. Pressing the pushbutton down slightly causes the connections to the anchor to break andcauses the pin to slide through the aperture into a partially insertedposition. In this pre-loaded state, the fastener can be easily insertedinto the items to be fastened, and then only a small pressing motion onthe push pin can move the fastener into a fully locked position. Priorto achieving the fully locked position, the pin can freely move up anddown within the anchor. There are preferably grooves on the pin thatlock into protrusions located underneath the top plate after the pin hasbeen fully inserted in the top plate, to prevent the pin from slidingback up out of the apertures after full insertion into the anchor.

[0017] The open V-shape of the anchor arms gives them extra flexibilityso that insertion of the pin into apertures in the items to be fastenedis simple and does not require a lot of force. Similarly, pressing thepush pin into the anchor legs does not require a lot of force for thelegs to extend outward and lock the fastener to the items to befastened,

[0018] Because the fastener is molded with the pin and anchor alreadytogether, it does not require any assembly to use. Traditional two-pieceanchor systems require assembling of the pin and anchor prior to use,requiring additional time and causing additional operator fatigue. Inthe present invention, all that is required to use the anchor isdepressing the pin enough to break the connections and pre-load thefastener. This can be done on the manufacturing end or on the assemblyline.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Other objects and features of the present invention will becomeapparent from the following detailed description considered inconnection with the accompanying drawings. It is to be understood,however, that the drawings are designed as an illustration only and notas a definition of the limits of the invention

[0020] In the drawings, wherein similar reference characters denotesimilar elements throughout the several views:

[0021]FIG. 1 shows a perspective view of one embodiment of the fasteneraccording to the invention in a just-molded state;

[0022]FIG. 2 shows a front view of the fastener of FIG. 1;

[0023]FIG. 3 shows a front view of the fastener of FIG. 1 in apre-loaded state;

[0024]FIG. 4 shows a front view of the fastener installed on twosheet-like items, prior to locking;

[0025]FIG. 5 shows a front view of the fastener of FIG. 4 in apre-locking state on the items;

[0026]FIG. 6 shows a front view of the fastener of FIGS. 4 and 5 in afully locked position;

[0027]FIG. 7 shows a front view of the top plate and retaining arms ofthe anchor portion of the fastener of FIG. 1; and

[0028]FIG. 8 shows a bottom view of the push pin of the fastener shownin FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0029] Referring now in detail to the drawings, FIGS. 1-6 show thefastener 10 according to the invention as it goes from an initiallymolded state (FIG. 1) into a fully locked position (FIG. 6) FIGS. 1 and2 show the fastener 10 according to the invention in an initial moldedstate. Fastener 10 comprises an anchor 20 and a push pin assembly 30.Anchor 20 has a top plate 21 connected to a central leg 23. Central leg23 extends substantially perpendicular to the bottom surface of topplate 21. There are two flexible anchor arms 24 connected to the freeend of central leg 23. Each anchor arm 24 extends up and away fromcentral leg 23, and each anchor arm 24 has a free end 25 that is notconnected to anything. Anchor arm 24 has a tapered top portion 28 thatwidens as arm 24 extends from its free end 25 back toward the tip ofcentral leg 23, creating a slanted wall facing central leg 23.

[0030] Push pin assembly 30 comprises a push button 31 and a pin 32connected to and extending downward from the bottom surface of pushbutton 31. Pin 32 is adapted to fit through an aperture 22 in top plate21, such that pushing push button 31 causes pin 32 to extend through theaperture 22 and slide along the slanted wall of anchor arm 24 as pushbutton 31 is depressed to force anchor arms 24 to bend away from centralleg 23 and away from each other. (See FIGS. 4-6).

[0031] As shown in FIG. 1, and in greater detail in FIG. 8, pin portion32 has a channel 33 cut therein. Channel 33 corresponds in shape tocentral leg 23 of anchor 20, so that depressing push button 31 causespin 32 to slide along central leg 23 with the central leg 23 fitting atleast partially within channel 33 (See FIG. 8). This way, central leg23, in addition to supporting anchor arms 24, acts as a guide for pin32. Channel 33 is not shown in FIGS. 2-6, as it is facing away in thoseviews.

[0032] There are two retaining arms 40 extending down from the bottomsurface of top plate 21 As shown in FIGS. 5 and 6, retaining arms 40contact the free end 25 of anchor arms 24 when push button 31 is fullydepressed and prevent anchor arms 24 from extending out beyond apredetermined limit.

[0033] As shown in FIGS. 1-4, there is a latching mechanism comprising ahook 42 on free end 25 of retaining arms 40, as well as a correspondinghook 43 (shown in FIG. 1) on the free ends 25 of anchor arms 24. Hooks42 and 43 engage each other when push button 31 is fully depressed toprevent anchor arms 24 from escaping beyond retaining arms 40. There isa flange 41 located on an edge of retaining arms 40 (shown in detail inFIG. 7), which prevents any lateral movement of the anchor arms 24 whenarms 24 are in the fully extended position push button.

[0034] As shown in FIG. 1, there is a transversely extending guideflange 26 on an inside surface of anchor arms 24. Guide flange 26 guidespin 32 as it extends down toward anchor arms 24 and keeping pin 32oriented parallel to central leg 23. Preferably, one end of guide flange24 extends outwardly and around toward central leg 23 and preventslateral pivoting of pin 32, to prevent central leg 23 from coming out ofchannel 33 when push button 31 is depressed.

[0035]FIGS. 1 and 2 show fastener 10 in its initially molded state. Pushpin assembly 30 is integrally molded with anchor 20 via connectionpoints 36 connecting top plate 21 with a bottom section of pin 32. Asshown in FIG. 3, downward pressure on push button 31 causes connectionpoints 36 to break and pin 32 to extend through aperture 22 in top plate21. This action can be easily done at either the manufacturing level orat the installation site, prior to installation of fastener 10.

[0036]FIGS. 4-6 show the installation of fastener 10 on two flat items50 and 60. Typically, items 50 and 60 would be an automobile body paneland sheet metal, respectively, but any substantially flat item could befastened with fastener 10. As push button 31 is depressed and anchorarms are forced outwardly, this outward extension of anchor arms 24retains anchor 20 securely within items 50 and 60 (see FIGS. 5 and 6).

[0037] There is a locking mechanism to lock fastener 10 in a lockedposition on items 50 and 6O, which comprises notches 35 in pin 32. Thebottom of guide flange 26 on anchor arms 24 catch notches 35 to preventupward movement of pin 32 once push button 31 is fully depressed. Thereis a further set of notches 34 in pin 32, and a pair of flanges 48extending underneath the bottom surface of top plate 21. Depressing pushbutton 31 completely causes flanges 48 to snap into notches 35 andfurther prevent upward movement of push pin assembly 30.

[0038] It should be noted that enough vertical clearance must be allowedbetween hook 43 on arm 24 and flange 48, so that pressing legs 24together to force them through a hole in a panel causes the verticalextension of legs 24 to increase, and their width to narrow. Flange 48is positioned so as not to interfere with this movement of legs 24 asfastener 10 is inserted into an item to be fastened. In addition, hook43 is fashioned so that while it prevents further horizontal extensionof arms 24, it does not prevent arms 24 from being further compressed,if necessary. For example, as fastener 10 is placed into a pre-lockedposition shown in FIG. 5, hook 43 engages hook 24, but releasing pushbutton 31 prior to final locking may still allow legs 24 to becompressed and disengaged from hook 43.

[0039] The fastener according to the present invention requires noassembly, is simple to install, does not cause extensive operatorfatigue and allows for reliable fastening of two or more planar itemstogether.

[0040] Accordingly, while only a single embodiment of the presentinvention has been shown and described, it is obvious that many changesand modifications may be made there unto without departing from thespirit and scope of the invention.

1. A fastener comprising: an anchor comprising: (a) a top plate having atop surface and a bottom surface; (b) a central leg connected to andextending substantially perpendicular to the bottom surface of the topplate, said central leg having a free end; and (c) at least one anchorarm connected to the free end of the central leg, said anchor armextending up and away from the central leg and having a free end, saidfree end not being connected to anything; and a push pin assemblycomprising: a push button having a top surface and a bottom surface; apin portion connected to and extending downward from the bottom surfaceof the push button, said pin being adapted to fit through an aperture inthe top plate, such that pushing the push button causes the pin portionto extend through the aperture parallel to the central leg and force theat least one anchor arm further outwardly; and a locking device forlocking the push pin in a depressed state.
 2. The fastener according toclaim 1, further comprising a least one retaining arm extending downfrom the bottom surface of the top plate, said at least one retainingarm contacting the free end of the at least one anchor arm when the pushbutton is fully depressed and preventing the at least one anchor armfrom extending out beyond a predetermined limit.
 3. The fasteneraccording to claim 2, further comprising a latching mechanism on thefree end of the at least one anchor arm and the at least one retainingarm, said latching mechanism engaging when said push button is fullydepressed to prevent the anchor arm from escaping beyond the retainingarm.
 4. The fastener according to claim 3, wherein the latchingmechanism is a hook on the retaining arm and a corresponding oppositelyoriented hook on the anchor arm, said two hooks interlocking when saidpush button is fully depressed.
 5. The fastener according to claim 2,further comprising a flange located on an edge of the at least oneretaining arm, said flange preventing any lateral movement of the atleast one anchor arm when the push button is fully depressed.
 6. Thefastener according to claim 1, wherein the pin has a channel cuttherein, the channel corresponding in shape to the central leg of theanchor, wherein depressing the push button causes the pin to slide alongthe central leg with the central leg fitting at least partially withinthe channel.
 7. The fastener according to claim 1, wherein the aperturehas a shape that corresponds to a cross-sectional shape of the pin. 8.The fastener according to claim 6, further comprising a transverselyextending guide flange on an inside surface of said at least one anchorarm, said guide flange guiding the pin as it extends down toward the atleast one anchor arm and keeping the pin oriented parallel to thecentral leg.
 9. The fastener according to claim 8, wherein one end ofthe guide flange extends outwardly toward the central leg and preventsthe central leg from coming out of the channel when the push button isdepressed.
 10. The fastener according to claim 1, wherein the push pinassembly is integrally molded with the anchor via connection pointsconnecting the top plate with a bottom portion of the pin, and whereindownward pressure on the push button causes the connection points tobreak and the pin to extend through the aperture in the top plate. 11.The fastener according to claim 1, wherein there are at least two anchorarms.
 12. The fastener according to claim 1, wherein the at least oneanchor arm has a tapered free end that widens as the arm extends towardthe central leg, creating a slanted wall facing the central leg, andwherein the pin slides along the slanted wall as the push button isdepressed and forces the at least one anchor arm to bend away from thecentral leg.
 13. The fastener according to claim 8, wherein the lockingdevice comprises at least one notch in the pin, said guide flange on theat least one anchor arm catching in said notch and preventing upwardmovement of the pin once the push button is fully depressed.
 14. Thefastener according to claim 13, wherein the locking mechanism furthercomprises at least one notch in the pin and at least one flangeextending underneath the bottom surface of the top plate, whereindepressing the push button completely causes the at least one flangeunderneath the bottom surface to snap into the at least one notch andprevent upward movement of the push pin assembly.